Facial Action Coding System (FACS): Definition, History, and Characteristics
Facial Action Coding System (FACS) is an anatomical-based system used to measure and describe facial movement. Developed in the late 1970s by psychologist Paul Ekman and Wallace V. Friesen, FACS is a tool used to objectively measure facial expressions and behaviors. The purpose of FACS is to enable researchers to accurately quantify, and differentiate between, subtle facial expressions and movements, as well as to assess and compare facial expressions across different individuals.
FACS was developed as a tool to study the relationship between facial expressions and emotions. To create FACS, Ekman and Friesen used a combination of anatomy, physiology, and psychology to observe and quantify facial movements. They identified and categorized all visible facial movements into a set of universal facial actions called “Action Units” (AUs). There are 46 AUs in total, divided into two major categories: action descriptors (AUs that describe the type and intensity of the movement) and action modifiers (AUs that modify other AUs in terms of direction, intensity, or speed).
FACS has been used to study a variety of phenomena, including nonverbal communication, facial expressions of emotion, facial coordination and development, and facial dynamics. The tool has proven to be a reliable and valid measure of facial expression and behavior, providing researchers with a standard way to measure and analyze facial expressions.
FACS has been widely used in the field of psychology, as well as other disciplines, including medicine, anthropology, and linguistics. The tool has been applied to a variety of research contexts, such as the study of emotion recognition, facial mimicry, and facial communication.
FACS is an important tool for understanding facial behavior and expression. The system has been used to inform research on facial movement, facial recognition, and the role of facial expressions in communication. As the field of facial research continues to evolve, FACS is expected to remain an important tool for measuring and analyzing facial behavior and expression.
References
Ekman, P., & Friesen, W. V. (2002). The Facial Action Coding System (2nd ed.). Salt Lake City, UT: Research Nexus eBook.
Gauthier, I., & Tarr, M. J. (Eds.). (2017). The Oxford Handbook of Face Perception. Oxford: Oxford University Press.
Lundqvist, D., & Lunderqvist, A. (2017). The Facial Action Coding System (FACS): A brief review. Emotion Review, 9(2), 132-139. https://doi.org/10.1177/1754073916662093
Picard, R. W., & Kemp, C. (Eds.). (2002). Affective Computing. Cambridge, MA: MIT Press.
Sato, W., & Yoshikawa, S. (2001). Facial Action Coding System (FACS): A nonverbal measure of emotion. In D. Matsumoto (Ed.), The Handbook of Nonverbal Communication (pp. 143-164). Thousand Oaks, CA: Sage.